NEWS 88.2 KB
Newer Older
1
2
New in spot 1.99.1a (not yet released)

3
4
  * Bugs fixed:
    - p[+][:*2] was not detected as belonging to siPSL
5
6
    - scc_filter() would incorrectly remove Fin marks from
      rejecting SCCs.
7

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
8
New in spot 1.99.1 (2015-06-23)
9

10
11
12
13
14
  * Major changes motivating the jump in version number

    - Spot now works with automata that can represent more than
      generalized Büchi acceptance.  Older versions were built around
      the concept of TGBA (Transition-based Generalized Büchi
15
      Automata) while this version now deals with what we call TωA
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
      (Transition-based ω-Automata).  TωA support arbitrary acceptance
      conditions specified as a Boolean formula of transition sets
      that must be visited infinitely often or finitely often.  This
      genericity allows for instance to represent Rabin or Streett
      automata, as well as some generalized variants of those.

    - Spot has near complete support for the Hanoi Omega Automata
      format.  http://adl.github.io/hoaf/  This formats supports
      automata with the generic acceptance condition described above,
      and has been implemented in a number of third-party tools (see
      http://adl.github.io/hoaf/support.html) to ease their
      interactions.  The only part of the format not yet implemented in
      Spot is the support for alternating automata.

    - Spot is now compiling in C++11 mode.  The set of C++11 features
      we use requires GCC >= 4.8 or Clang >= 3.5.  Although GCC 4.8 is
      more than 2-year old, people with older installations won't be
      able to install this version of Spot.

35
    - As a consequence of the switches to C++11 and to TωA, a lot of
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
      the existing C++ interfaces have been renamed, and sometime
      reworked.  This makes this version of Spot not backward
      compatible with Spot 1.2.x.  See below for the most important
      API changes.  Furtheremore, the reason this release is not
      called Spot 2.0 is that we have more of those changes planned.

    - Support for Python 2 was dropped.  We now support only Python
      3.2 or later.  The Python bindings have been improved a lot, and
      include some conveniance functions for better integration with
      IPython's rich display system.  User familiar with IPython's
      notebook should have a look at the notebook files in
      wrap/python/tests/*.ipynb

  * Major news for the command-line tools

    - The set of tools installed by spot now consists in the following
      11 commands.  Those marked with a '+' are new in this release.

      - randltl    Generate random LTL/PSL formulas.
      - ltlfilt    Filter and convert LTL/PSL formulas.
      - genltl     Generate LTL formulas from scalable patterns.
      - ltl2tgba   Translate LTL/PSL formulas into Büchi automata.
      - ltl2tgta   Translate LTL/PSL formulas into Testing automata.
      - ltlcross   Cross-compare LTL/PSL-to-Büchi translators.
      + ltlgrind   Mutate LTL/PSL formula.
      - dstar2tgba Convert deterministic Rabin or Streett automata into Büchi.
      + randaut    Generate random automata.
      + autfilt    Filter and convert automata.
      + ltldo      Run LTL/PSL formulas through other tools.

      randaut does not need any presentation: it does what you expect.

      ltlgrind is a new tool that mutates LTL or PSL formulas.  If you
69
      have a tool that is bogus on some formula that is too large to
70
71
72
      debug, you can use ltlgrind to generate smaller derived formulas
      and see if you can reproduce the bug on those.

73
74
75
76
77
78
79
80
81
82
83
84
      autfilt is a new tool that processes a stream of automata.  It
      allows format conversion, filtering automata based on some
      properties, and general transformations (e.g., change of
      acceptance conditions, removal of useless states, product
      between automata, etc.).

      ltldo is a new tool that runs LTL/PSL formulas through other
      tools, but uses Spot's command-line interfaces for specifying
      input and output.  This makes it easier to use third-party tool
      in a pipe, and it also takes care of some necessary format
      conversion.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
85
    - ltl2tgba has a new option, -U, to produce unambiguous automata.
86
87
88
      In unambiguous automata any word is recognized by at most one
      accepting run, but there might be several ways to reject a word.
      This works for LTL and PSL formulas.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
89

90
    - ltl2tgba has a new option, -S, to produce generalized-Büchi
91
92
93
94
95
      automata with state-based acceptance.  Those are obtained by
      converting some transition-based GBA into a state-based GBA, so
      they are usually not as small as one would wish.  The same
      option -S is also supported by autfilt.

96
97
98
99
100
    - ltlcross will work with translator producing automata with any
      acceptance condition, provided the output is in the HOA format.
      So it can effectively be used to validate tools producing Rabin
      or Streett automata.

101
    - ltlcross has several new options:
102

103
104
        --grind attempts to reduce the size of any bogus formula it
        discovers, while still exhibiting the bug.
105

106
107
        --ignore-execution-failures ignores cases where a translator
        exits with a non-zero status.
108
109

	--automata save the produced automata into the CSV or JSON
110
        file.  Those automata are saved using the HOA format.
111
112
113
114
115

      ltlcross will also output two extra columns in its CSV/JSON
      output: "ambiguous_aut" and "complete_aut" are Boolean
      that respectively tells whether the automaton is
      ambiguous and complete.
116

117
    - "ltlfilt --stutter-invariant" will now work with PSL formulas.
118
      The implementation is actually much more efficient
119
      than our previous implementation that was only for LTL.
120

121
122
123
124
125
    - ltlfilt's old -q/--quiet option has been renamed to
      --ignore-errors.  The new -q/--quiet semantic is the
      same as in grep (and also autfilt): disable all normal
      input, for situtations where only the exit status matters.

126
127
128
129
    - ltlfilt's old -n/--negate option can only be used as --negate
      now.  The short '-n NUM' option is now the same as the new
      --max-count=N option, for consistency with other tools.

130
131
132
    - ltlfilt has a new --count option to count the number of matching
      automata.

133
134
135
    - ltlfilt has a new --exclusive-ap option to constrain formulas
      based on a list of mutually exclusive atomic propositions.

136
137
138
139
    - ltlfilt has a new option --define to be used in conjunction with
      --relabel or --relabel-bool to print the mapping between old and
      new labels.

140
141
142
143
144
145
    - all tools that produce formulas or automata now have an --output
      (a.k.a. -o) option to redirect that output to a file instead of
      standard output.  The name of this file can be constructed using
      the same %-escape sequences that are available for --stats or
      --format.

146
147
148
149
    - all tools that output formulas have a -0 option to separate
      formulas with \0.  This helps in conjunction with xargs -0.

    - all tools that output automata have a --check option that
150
151
152
153
154
155
156
157
158
159
      request extra checks to be performed on the output to fill
      in properties values for the HOA format.  This options
      implies -H for HOA output.  For instance
      	ltl2tgba -H 'formula'
      will declare the output automaton as 'stutter-invariant'
      only if the formula is syntactically stutter-invariant
      (e.g., in LTL\X).  With
        ltl2tgba --check 'formula'
      additional checks will be performed, and the automaton
      will be accurately marked as either 'stutter-invariant'
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
160
161
      or 'stutter-sensitive'.  Another check performed by
      --check is testing whether the automaton is unambiguous.
162

163
164
165
166
167
168
    - ltlcross (and ltldo) have a list of hard-coded shorthands
      for some existing tools.  So for instance running
      'ltlcross spin ...' is the same as running
      'ltlcross "spin -f %s>%N" ...'.   This feature is much
      more useful for ltldo.

169
170
    - For options that take an output filename (i.e., ltlcross's
      --save-bogus, --grind, --csv, --json) you can force the file
171
172
      to be opened in append mode (instead of being truncated) by
      by prefixing the filename with ">>".  For instance
173
174
175
      	  --save-bogus=">>bugs.ltl"
      will append to the end of the file.

176
177
  * Other noteworthy news

178
179
180
181
182
183
184
185
    - The web site moved to http://spot.lrde.epita.fr/.

    - We now have Debian packages.
      See http://spot.lrde.epita.fr/install.html

    - The documentation now includes some simple code examples
      for both Python and C++.  (This is still a work in progress.)

186
187
188
189
    - The curstomized version of BuDDy (libbdd) used by Spot has be
      renamed as (libbddx) to avoid issues with copies of BuDDy
      already installed on the system.

190
191
    - There is a parser for the HOA format
      (http://adl.github.io/hoaf/) available as a
192
193
194
195
196
197
      spot::automaton_stream_parser object or spot::parse_aut()
      function.  The former version is able to parse a stream of
      automata in order to do batch processing.  This format can be
      output by all tools (since Spot 1.2.5) using the --hoa option,
      and it can be read by autfilt (by default) and ltlcross (using
      the %H specifier).  The current implementation does not support
198
199
      alternation.  Multiple initial states are converted into an
      extra initial state; complemented acceptance sets Inf(!x) are
200
201
      converted to Inf(x); explicit or implicit labels can be used;
      aliases are supported; "--ABORT--" can be used in a stream.
202

203
204
205
206
207
208
    - The above HOA parser can also parse never claims, and LBTT
      automata, so the never claim parser and the LBTT parser have
      been removed.  This implies that autfilt can input a mix of HOA,
      never claims, and LBTT automata.  ltlcross also use the same
      parser for all these output, and the old %T and %N specifiers
      have been deprecated and replaced by %O (for output).
209

210
211
    - While not all algorithms in the library are able to work with
      any acceptance condition supported by the HOA format, the
212
      following two new functions mitigate that:
213
214
215
216
217
218
219
220
221
222

      - remove_fin() takes a TωA whose accepting condition uses Fin(x)
	primitive, and produces an equivalent TωA without Fin(x):
	i.e., the output acceptance is a disjunction of generalized
	Büchi acceptance.  This type of acceptance is supported by
	SCC-based emptiness-check, for instance.

      - similarly, to_tgba() converts any TωA into an automaton with
	generalized-Büchi acceptance.

223
224
225
    - randomize() is a new algorithm that randomly reorders the states
      and transitions of an automaton.  It can be used from the
      command-line using "autfilt --randomize".
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
226

227
228
    - the interface in iface/dve2 has been renamed to iface/ltsmin
      because it can now interface the dynamic libraries created
229
      either by Divine (as patched by the LTSmin group) or by
230
231
      Spins (the LTSmin compiler for Promela).

232
233
234
235
236
237
238
239
    - LTL/PSL formulas can include /* comments */.

    - PSL SEREs support a new operator [:*i..j], the iterated fusion.
      [:*i..j] is to the fusion operator ':' what [*i..j] is to the
      concatenation operator ';'.  For instance (a*;b)[:*3] is the
      same as (a*;b):(a*;b):(a*;b).  The operator [:+], is syntactic
      sugar for [:*1..], and corresponds to the operator ⊕ introduced
      by Dax et al. (ATVA'09).
240

241
242
243
244
245
246
    - GraphViz output now uses an horizontal layout by default, and
      also use circular states (unless the automaton has more than 100
      states, or uses named-states).  The --dot option of the various
      command-line tools takes an optional parameter to fine-tune the
      GraphViz output (including vertical layout, forced circular or
      elliptic states, named automata, SCC information, ordered
247
248
249
250
      transitions, and different ways to colorize the acceptance
      sets).  The environment variables SPOT_DOTDEFAULT and
      SPOT_DOTEXTRA can also be used to respectively provide a default
      argument to --dot, and add extra attributes to the output graph.
251

252
    - Never claims can now be output in the style used by Spin since
253
254
255
256
257
258
      version 6.2.4 (i.e., using do..od instead of if..fi, and with
      atomic statements for terminal acceptance).  The default output
      is still the old one for compatibility with existing tools.  The
      new style can be requested from command-line tools using option
      --spin=6 (or -s6 for short).

259
    - Support for building unambiguous automata.  ltl_to_tgba() has a
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
260
261
262
263
      new options to produce unambiguous TGBA (used by ltl2tgba -U as
      discussed above).   The function is_unambiguous() will check
      whether an automaton is unambigous, and this is used by
      autfilt --is-unmabiguous.
264

265
266
267
268
269
270
271
272
    - The SAT-based minimization algorithm for deterministic automata
      has been updated to work with ω-Automaton with any acceptance.
      The input and the output acceptance can be different, so for
      instance it is possible to create a minimal deterministic
      Streett automaton starting from a deterministic Rabin automaton.
      This functionnality is available via autfilt's --sat-minimize
      option.  See doc/userdoc/satmin.html for details.

273
274
275
    - The on-line interface at http://spot.lrde.epita.fr/trans.html
      can be used to check stutter-invariance of any LTL/PSL formula.

276
277
278
279
    - The on-line interface will work around atomic propositions not
      supported by ltl3ba.  (E.g. you can now translate F(A) or
      G("foo < bar").)

280
  * Noteworthy code changes
281
282
283

    - Boost is not used anymore.

284
285
286
287
288
289
290
291
292
293
294
295
296
    - Automata are now manipulated exclusively via shared pointers.

    - Most of what was called tgba_something is now called
      twa_something, unless it is really meant to work only for TGBA.
      This includes functions, classes, file, and directory names.
      For instance the class tgba originally defined in tgba/tgba.hh,
      has been replaced by the class twa defined in twa/twa.hh.

    - the tgba_explicit class has been completely replaced by a more
      efficient twa_graph class.  Many of the algorithms that were
      written against the abstract tgba (now twa) interface have been
      rewritten using twa_graph instances as input and output, making
      the code a lot simpler.
297

298
299
300
    - The tgba_succ_iterator (now twa_succ_iterator) interface has
      changed.  Methods next(), and first() should now return a bool
      indicating whether the current iteration is valid.
301

302
303
    - The twa base class has a new method, release_iter(), that can
      be called to give a used iterator back to its automaton.  This
304
305
306
307
      iterator is then stored in a protected member, iter_cache_, and
      all implementations of succ_iter() can be updated to recycle
      iter_cache_ (if available) instead of allocating a new iterator.

308
309
310
    - The tgba (now called twa) base class has a new method, succ(),
      to support C++11' range-based for loop, and hide all the above
      change.
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333

      Instead of the following syntax:

	tgba_succ_iterator* i = aut->succ_iter(s);
	for (i->first(); !i->done(); i->next())
	  {
	     // use i->current_state()
	     //     i->current_condition()
	     //     i->current_acceptance_conditions()
	  }
	delete i;

      We now prefer:

	for (auto i: aut->succ(s))
	  {
	    // use i->current_state()
	    //     i->current_condition()
	    //     i->current_acceptance_conditions()
	  }

      And the above syntax is really just syntactic suggar for

334
	twa_succ_iterator* i = aut->succ_iter(s);
335
336
337
338
339
340
341
342
343
344
345
346
	if (i->first())
	  do
	    {
	      // use i->current_state()
	      //     i->current_condition()
	      //     i->current_acceptance_conditions()
	    }
	  while (i->next());
	aut->release_iter(i); // allow the automaton to recycle the iterator

      Where the virtual calls to done() and delete have been avoided.

347
    - twa::succ_iter() now takes only one argument.  The optional
348
349
350
351
352
353
354
355
356
      global_state and global_automaton arguments have been removed.

    - The following methods have been removed from the TGBA interface and
      all their subclasses:
        - tgba::support_variables()
	- tgba::compute_support_variables()
	- tgba::all_acceptance_conditions()       // use acc().accepting(...)
	- tgba::neg_acceptance_conditions()
	- tgba::number_of_acceptance_conditions() // use acc().num_sets()
357

358
    - Membership to acceptance sets are now stored using bit sets,
359
      currently limited to 32 bits.  Each TωA has a acc() method that
360
361
362
363
      returns a reference to an acceptance object (of type
      spot::acc_cond), able to operate on acceptance marks
      (spot::acc_cond::mark_t).

364
      Instead of writing code like
365
366
367
        i->current_acceptance_conditions() == aut->all_acceptance_conditions()
      we now write
        aut->acc().accepting(i->current_acceptance_conditions())
368
      (Note that for accepting(x) to return something meaningful, x
369
      should be a set of acceptance sets visitied infinitely often.  So let's
370
      imagine that in the above example i is looking at a self-loop.)
371
372
373
374
375
376

      Similarly,
        aut->number_of_acceptance_conditions()
      is now
        aut->acc().num_sets()

377
378
379
380
381
382
383
384
385
386
387
    - All functions used for printing LTL/PSL formulas or automata
      have been renamed to print_something().  Likewise the various
      parsers should be called parse_something() (they haven't yet
      all been renamed).

    - All test suites under src/ have been merged into a single one in
      src/tests/.  The testing tool that was called
      src/tgbatest/ltl2tgba has been renamed as src/tests/ikwiad
      (short for "I Know What I Am Doing") so that users should be
      less tempted to use it instead of src/bin/ltl2tgba.

388
389
  * Removed features

390
    - The long unused interface to GreatSPN (or rather, interface to
391
      a non-public, customized version of GreatSPN) has been removed.
392
      As a consequence, we could get rid of many cruft in the
393
394
      implementation of Couvreur's FM'99 emptiness check.

395
396
397
398
399
400
401
402
403
404
405
    - Support for symbolic, BDD-encoded TGBAs has been removed.  This
      includes the tgba_bdd_concrete class and associated supporting
      classes, as well as the ltl_to_tgba_lacim() LTL translation
      algorithm.  Historically, this TGBA implementation and LTL
      translation were the first to be implemented in Spot (by
      mistake!) and this resulted in many bad design decisions.  In
      practice they were of no use as we only work with explicit
      automata (i.e. not symbolic) in Spot, and those produced by
      these techniques are simply too big.

    - All support for ELTL, i.e., LTL logic extended with operators
406
      represented by automata has been removed.  It was never used in
407
408
409
410
      practice because it had no practical user interface, and the
      translation was a purely-based BDD encoding producing huge
      automata (when viewed explictely), using the above and non
      longuer supported tgba_bdd_concrete class.
411

412
    - Our implementation of the Kupferman-Vardi complementation has
413
      been removed: it was unused in practice beause of the size of
414
415
416
      the automata built, and it did not survive the conversion of
      acceptance sets from BDDs to bitsets.

417
418
    - The unused implementation of state-based alternating Büchi
      automata has been removed.
419

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
420
421
422
423
424
    - Input and output in the old, Spot-specific, text format for
      TGBA, has been fully removed.  We now use HOA everywhere.  (In
      case you have a file in this format, install Spot 1.2.6 and use
      "src/tgbatest/ltl2tgba -H -X file" to convert the file to HOA.)

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
425
New in spot 1.2.6 (2014-12-06)
426

427
428
429
  * New features:

    - ltlcross --verbose is a new option to see what is being done
430

431
432
  * Bug fixes:

433
434
435
436
    - Remove one incorrect simplification rule for PSL discovered
      via checks on random formulaes.  (The bug was very unlikely
      to trigger on non-random formulas, because it requires a SERE
      with an entire subexpression that is unsatisfiable.)
437
438
439
440
441
442
    - When the automaton resulting from the translation of a positive
      formula is deterministic, ltlcross will compute its complement
      to perform additional checks against other translations of the
      positive formula.  The same procedure should be performed with
      automata obtained from negated formulas, but because of a typo
      this was not the case.
443
444
    - the neverclaim parser will now diagnose redefinitions of
      state labels.
445
446
    - the acceptance specification in the HOA format output have been
      adjusted to match recent changes in the format specifications.
447
    - atomic propositions are correctly escaped in the HOA output.
448
449
450
451
    - the build rules for documentation have been made compatible with
      version 8.0 of Org-mode.  (This was only a problem if you build
      from the git repository, or if you want to edit the
      documentation.)
452
453
454
455
    - recent to changes to libstd++ (as shipped by g++ 4.9.2) have
      demonstrated that the order of transitions output by the
      LTL->TGBA translation used to be dependent on the implementation
      of the STL.  This is now fixed.
456
457
458
459
460
    - some developpement version of libstd++ had a bug (PR 63698) in
      the assignment of std::set, and that was triggered in two places
      in Spot.  The workaround (not assigning sets) is actually more
      efficient, so we can consider it as a bug fix, even though
      libstd++ has also been fixed.
461
462
    - all parsers would report wrong line numbers while processing
      files with DOS style newlines.
463
    - add support for SWIG 3.0.
464

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
465
New in spot 1.2.5 (2014-08-21)
466

467
  * New features:
468
469
470

    - The online ltl2tgba translator will automatically attempt to
      parse a formula using LBT's syntax if it cannot parse it using
471
472
      the normal infix syntax.  It also has an option to display
      formulas using LBT's syntax.
473

474
475
476
477
478
479
    - ltl2tgba and dstar2tgba have a new experimental option --hoaf to
      output automata in the Hanoï Omega Automaton Format whose
      current draft is at http://adl.github.io/hoaf/
      The corresponding C++ function is spot::hoaf_reachable() in
      tgbaalgos/hoaf.hh.

480
481
    - 'randltl 4' is now a shorthand for 'randltl p0 p1 p2 p3'.

482
483
484
485
    - ltlcross has a new option --save-bogus=FILENAME to save any
      formula for which a problem (other than timeout) was detected
      during translation or using the resulting automatas.

486
  * Documentation:
487
488
489
490

    - The man page for ltl2tgba has some new notes and references
      about TGBA and about monitors.

491
492
  * Bug fixes:

493
494
495
496
    - Fix incorrect simplification of promises in the translation
      of the M operator (you may suffer from the bug even if you do
      not use this operator as some LTL patterns are automatically
      reduced to it).
497
    - Fix simplification of bounded repetition in SERE formulas.
498
499
500
    - Fix incorrect translation of PSL formulas of the form !{f} where
      f is unsatisifable.  A similar bug was fixed for {f} in Spot
      1.1.4, but for some reason it was not fixed for !{f}.
501
    - Fix parsing of neverclaims produced by Modella.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
502
503
504
    - Fix a memory leak in the little-used conversion from
      transition-based alternating automata to tgba.
    - Fix a harmless uninitialized read in BuDDy.
505
506
507
508
509
    - When writing to the terminal, ltlcross used to display each
      formula in bright white, to make them stand out.  It turns out
      this was actually hiding the formulas for people using a
      terminal with white background... This version displays formula
      in bright blue instead.
510
511
512
513
    - 'randltl -n -1 --seed 0' and 'randltl -n -1 --seed 1' used to
      generate nearly the same list of formulas, shifted by one,
      because the PRNG write reset with an incremented seed between
      each output formula.  The PRNG is now reset only once.
514

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
515
New in spot 1.2.4 (2014-05-15)
516

517
518
519
  * New features:

    - "-B -x degen-lskip" can be used to disable level-skipping in the
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
520
521
      degeralization procedure called by ltl2tgba and dstar2tgba.
      This is mostly meant for running experiments.
522
523
524
525
526
527
    - "-B -x degen-lcache=N" can be used to experiment with different
      type of level caching during degeneralization.

  * Bug fixes:

    - Change the Python bindings to make them compatible with Swig 3.0.
528
529
530
    - "ltl2tgta --ta" could crash in certain conditions due to the
      introduction of a simulation-based reduction after
      degeneralization.
531
532
533
534
535
    - Fix four incorrect formula-simplification rules, three were
      related to the factorization of Boolean subformulas in
      operands of the non-length-matching "&" SERE operator, and
      a fourth one could only be enabled by explicitely passing the
      favor_event_univ option to the simplifier (not the default).
536
537
    - Fix incorrect translation of the fusion operator (":") in SERE
      such as {xx;1}:yy[*] where the left operand has 1 as tail.
538

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
539
New in spot 1.2.3 (2014-02-11)
540

541
542
543
544
545
  * New features:

    - The SPOT_SATLOG environment variable can be set to a filename to
      obtain statistics about the different iterations of the
      SAT-based minimization.  For an example, see
546
      http://spot.lrde.epita.fr/satmin.html
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
547
548
    - The bench/dtgbasat/ benchmark has been updated to use SPOT_SATLOG
      and record more statistics.
549
550
551
552
    - The default value for the SPOT_SATSOLVER environment
      variable has been changed to "glucose -verb=0 -model %I >%O".
      This assumes that glucose 3.0 is installed.   For older
      versions of glucose, remove the "-model" option.
553

554
555
556
  * Bug fixes:

    - More fixes for Python 3 compatibility.
557
558
559
    - Fix calculation of length_boolone(), were 'Xa|b|c' was
      considered as length 6 instead of 4 (because it is 'Xa|(b|a)'
      were (b|a) is Boolean).
560
561
562
563
    - Fix Clang-3.5 warnings.
    - randltl -S did not honor --boolean-priorities.
    - randltl had trouble generating formulas when all unary, or
      all binary/n-ary operators were disabled.
564
    - Fix spurious testsuite failure when using Pandas 0.13.
565
566
567
568
569
    - Add the time spent in child processes when measuring time
      with the timer class.
    - Fix determinism of the SAT-based minimization encoding.
      (It would sometimes produce different equivalent automata,
      because of a different encoding order.)
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
570
571
    - If the SAT-based minimization is asked for a 10-state automaton
      and returns a 6-state automaton, do not ask for a 9-state
572
      automaton in the next iteration...
573
574
575
576
    - Fix some compilation issue with the version of Apple's Clang
      that is installed with MacOS X 10.9.
    - Fix VPATH builds when building from the git repository.
    - Fix UP links in the html documentation for command-line tools.
577

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
578
New in spot 1.2.2 (2014-01-24)
579

580
581
582
583
584
585
586
587
  * Bug fixes:

    - Fix compilation *and* behavior of bitvectors on 32-bit
      architectures.
    - Fix some compilation errors observed using the antique G++ 4.0.1.
    - Fix compatibility with Python 3 in the test suite.
    - Fix a couple of new clang warnings (like "unused private member").
    - Add some missing #includes that are not included indirectly
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
588
      when the C++ compiler is in C++11 mode.
589
590
591
592
    - Fix detection of numbers that are too large in the ELTL parser.
    - Fix a memory leak in the ELTL parser, and avoid some unnecessary
      calls to strlen() at the same time.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
593
New in spot 1.2.1 (2013-12-11)
594

595
  * New features:
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
596

597
598
599
600
601
602
    - commands for translators specified to ltlcross can now
      be given "short names" to be used in the CSV or JSON output.
      For instance
         ltlcross '{small} ltl2tgba -s --small %f >%N' ...
      will run the command "ltl2tgba -s --small %f >%N", but only
      print "small" in output files.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
603

604
605
606
607
608
609
610
    - ltlcross' CSV and JSON output now contains two additional
      columns: exit_status and exit_code, used to report failures of
      the translator.  If the translation failed, only the time is
      reported, and the rest of the statistics, which are missing,
      area left empty (in CVS) or null (in JSON).  A new option,
      --omit-missing can be used to remove lines for failed
      translations, and remove these two columns.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
611

612
613
614
    - if ltlcross is used with --products=+5 instead of --products=5
      then the stastics for each of the five products will be output
      separately instead of being averaged.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
615

616
617
618
619
620
    - if ltlcross is used with tools that produce deterministic Streett
      or Rabin automata (as specified with %D), then the statistics
      output in CSV or JSON will have some extra columns to report
      the size of these input automata before ltlcross converts them
      into TGBA to perform its regular checks.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
621

622
623
624
625
    - ltlfilt, ltl2tgba, ltl2tgta, and ltlcross can now read formulas
      from CSV files.  Use option -F FILE/COL to read formulas from
      column COL of FILE.  Use -F FILE/-COL if the first line of
      FILE be ignored.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
626

627
628
629
630
631
    - when ltlfilt processes formulas from a CSV file, it will output
      each CSV line whose formula matches the given constraints, with
      the rewriten formula.  The new escape sequence %< (text in
      columns before the formula) and %> (text after) can be used
      with the --format option to alter this output.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
632

633
634
    - ltlfile, genltl, randltl, and ltl2tgba have a --csv-escape option
      to help escape formulas in CSV files.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
635

636
    - Please check
637
            http://spot.lrde.epita.fr/csv.html
638
      for some discussion and examples of the last few features.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
639

640
  * Bug fixes:
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
641

642
643
644
645
646
647
    - ltlcross' CSV output has been changed to be more RFC 4180
      compliant: it no longuer output useless cosmetic spaces, and
      use double-quotes with proper escaping for strings.  The only
      RFC 4180 rule that it does not follow is that it will terminate
      lines with \n instead of \r\n because the latter cause issues
      with a couple of tools.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
648

649
650
    - ltlcross failed to report missing input or output escape sequences
      on all but the first configured translator.
651

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
652
New in spot 1.2 (2013-10-01)
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
653

654
655
656
657
658
659
660
661
  * Changes to command-line tools:

    - ltlcross has a new option --color to color its output.  It is
      enabled by default when the output is a terminal.

    - ltlcross will give an example of infinite word accepted by the
      two automata when the product between a positive automaton and a
      negative automaton is non-empty.
662

663
664
    - ltlcross can now read the Rabin and Streett automata output by
      ltl2dstar.  This type of output should be specified using '%D':
665

666
        ltlcross 'ltl2dstar --ltl2nba=spin:path/to/ltl2tgba@-s %L %D'
667

668
      However because Spot only supports Büchi acceptance, these Rabin
669
      and Streett automata are immediately converted to TGBAs before
670
671
      further processing by ltlcross.  This is still interesting to
      search for bugs in translators to Rabin or Streett automata, but
672
      the statistics (of the resulting TGBAs) might not be very relevant.
673

674
675
676
677
678
679
    - When ltlcross obtains a deterministic automaton from a
      translator it will now complement this automaton to perform
      additional intersection checks.  This is complementation is done
      only for deterministic automata (because that is cheap) and can
      be disabled with --no-complement.

680
681
682
683
    - To help with debugging problems detected by ltlcross, the
      environment variables SPOT_TMPDIR and SPOT_TMPKEEP control where
      temporary files are created and if they should be erased.  Read
      the man page of ltlcross for details.
684

685
    - There is a new command, named dstar2tgba, that converts a
686
687
688
689
690
691
692
693
694
695
696
697
      deterministic Rabin or Streett automaton (expressed in the
      output format of ltl2dstar) into a TGBA, BA or Monitor.

      In the case of Rabin acceptance, the conversion will output a
      deterministic Büchi automaton if one such automaton exist.  Even
      if no such automaton exists, the conversion will actually
      preserves the determinism of any SCC that can be kept
      deterministic.

      In the case of Streett acceptance, the conversion produces
      non-deterministic Büchi automata with Generalized acceptance.
      These are then degeneralized if requested.
698

699
      See http://spot.lrde.epita.fr/dstar2tgba.html for some
700
701
      examples, and the man page for more reference.

702
703
704
705
706
    - The %S escape sequence used by ltl2tgba --stats to display the
      number of SCCs in the output automaton has been renamed to %c.
      This makes it more homogeneous with the --stats option of the
      new dstar2tgba command.

707
      Additionally, the %p escape can now be used to show whether the
708
709
710
      output automaton is complete, and the %r escape will give the
      number of seconds spent building the output automaton (excluding
      the time spent parsing the input).
711

712
713
714
715
716
    - ltl2tgba, ltl2tgta, and dstar2tgba have a --complete option
      to output complete automata.

    - ltl2tgba, ltl2tgta, and dstar2tgba can use a SAT-solver to
      minimize deterministic automata.  Doing so is only needed on
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
717
718
      properties that are stronger than obligations (for obligations
      our WDBA-minimization procedure will return a minimimal
719
720
721
      deterministic automaton more efficiently) and is disabled by
      default.  See the spot-x(7) man page for documentation about the
      related options: sat-minimize, sat-states, sat-acc, state-based.
722
      See also http://spot.lrde.epita.fr/satmin.html for some
723
      examples.
724

725
726
727
728
    - ltlfilt, genltl, and randltl now have a --latex option to output
      formulas in a way that its easier to embed in a LaTeX document.
      Each operator is output as a command such as \U, \F, etc.
      doc/tl/spotltl.sty gives one possible definition for each macro.
729

730
731
732
733
    - ltlfilt, genltl, and randltl have a new --format option to
      indicate how to present the output formula, possibly with
      information about the input.

734
735
736
737
738
    - ltlfilt as a new option, --relabel-bool, to abstract independent
      Boolean subformulae as if they were atomic propositions.
      For instance "a & GF(c | d) & b & X(c | d)" would be rewritten
      as "p0 & GF(p1) & Xp1".

739
  * New functions and classes in the library:
740

741
742
    - dtba_sat_synthetize(): Use a SAT-solver to build an equivalent
      deterministic TBA with a fixed number of states.
743

744
745
    - dtba_sat_minimize(), dtba_sat_minimize_dichotomy(): Iterate
      dtba_sat_synthetize() to reduce the number of states of a TBA.
746

747
748
    - dtgba_sat_synthetize(), dtgba_sat_minimize(),
      dtgba_sat_minimize_dichotomy(): Likewise, for deterministic TGBA.
749

750
    - is_complete(): Check whether a TGBA is complete.
751

752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
    - tgba_complete(): Complete an automaton by adding a sink state
      if needed.

    - dtgba_complement(): Complement a deterministic TGBA.

    - satsolver(): Run an (external) SAT solver, honoring the
      SPOT_SATSOLVER environment variable if set.

    - tba_determinize(): Run a power-set construction, and attempt
      to fix the acceptance simulation to build a deterministic TBA.

    - dstar_parse(): Read a Streett or Rabin automaton in
      ltl2dstar's format.  Note that this format allows only
      deterministic automata.

    - nra_to_nba(): Convert a (possibly non-deterministic) Rabin
      automaton to a non-deterministic Büchi automaton.

    - dra_to_ba(): Convert a deterministic Rabin automaton to a Büchi
      automaton, preserving acceptance in all SCCs where this is possible.

    - nsa_to_tgba(): Convert a (possibly non-deterministic) Streett
      automaton to a non-deterministic TGBA.

    - dstar_to_tgba(): Convert any automaton returned by dstar_parse()
      into a TGBA.

    - build_tgba_mask_keep(): Build a masked TGBA that shows only
      a subset of states of another TGBA.

    - build_tgba_mask_ignore(): Build a masked TGBA that ignore
      a subset of states of another TGBA.

    - class tgba_proxy: Helps writing on-the-fly algorithms that
      delegate most of their methods to the original automaton.

    - class bitvect: A dynamic bit vector implementation.

    - class word: An infinite word, stored as prefix + cycle, with a
      simplify() methods to simplify cycle and prefix in obvious ways.

    - class temporary_file: A temporary file.  Can be instanciated with
      create_tmp_file() or create_open_tmpfile().

    - count_state(): Return the number of states of a TGBA.  Implement
      a couple of specializations for classes where is can be know
      without exploration.

800
801
    - to_latex_string(): Output a formula using LaTeX syntax.

802
803
804
    - relabel_bse(): Relabeling of Boolean Sub-Expressions.
      Implements ltlfilt's --relabel-bool option describe above.

805
806
807
808
809
  * Noteworthy internal changes:

    - When minimize_obligation() is not given the formula associated
      to the input automaton, but that automaton is deterministic, it
      can still attempt to call minimize_wdba() and check the correcteness
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
810
811
      using dtgba_complement().  This allows dstar2tgba to apply
      WDBA-minimization on deterministic Rabin automata.
812
813
814

    - tgba_reachable_iterator_depth_first has been redesigned to
      effectively perform a DFS.  As a consequence, it does not
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
815
      inherit from tgba_reachable_iterator anymore.
816

817
818
819
820
    - postproc::set_pref() was used to accept an argument among Any,
      Small or Deterministic.  These can now be combined with Complete
      as Any|Complete, Small|Complete, or Deterministic|Complete.

821
822
823
824
825
    - operands of n-ary operators (like & and |) are now ordered so
      that Boolean terms come first.  This speeds up syntactic
      implication checks slightly.  Also, literals are now sorted
      using strverscmp(), so that p5 comes before p12.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
826
827
828
829
    - Syntactic implication checks have been generalized slightly
      (for instance 'a & b & F(a & b)' is now reduced to 'a & b'
      while it was not changed in previous versions).

830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
    - All the parsers implemented in Spot now use the same type to
      store locations.

    - Cleanup of exported symbols

      All symbols in the library now have hidden visibility on ELF systems.
      Public classes and functions have been marked explicitely for export
      with the SPOT_API macro.

      During this massive update, some of functions that should not have
      been made public in the first place have been moved away so that
      they can only be used from the library.  Some old of unused
      functions have been removed.

      removed:
	- class loopless_modular_mixed_radix_gray_code

      hidden:
	- class acc_compl
	- class acceptance_convertor
	- class bdd_allocator
	- class free_list

  * Bug fixes:

    - Degeneralization was not indempotant on automata with an
      accepting initial state that was on a cycle, but without
      self-loop.

    - Configuring with --enable-optimization would reset the value of
      CXXFLAGS.
861

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
862

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
863
New in spot 1.1.4 (2013-07-29)
864

865
866
867
868
869
  * Bug fixes:
    - The parser for neverclaim, updated in 1.1.3, would fail to
      parse guards of the form (a) || (b) output by ltl2ba or
      ltl3ba, and would only understand ((a) || (b)).
    - When used from ltlcross, the same parser would fail to
870
871
      parse further neverclaims after the first failure.
    - Add a missing newline in some error message of ltlcross.
872
873
874
875
876
877
878
    - Expressions like {SERE} were wrongly translated and simplified
      for SEREs that accept the empty word: they were wrongly reduced
      to true.  Simplification and translation rules have been fixed,
      and the doc/tl/tl.pdf specifications have been updated to better
      explain that {SERE} has the semantics of a closure operator that
      is not exactly what one could expect after reading the PSL
      standard.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
879
    - Various typos.
880

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
881
New in spot 1.1.3 (2013-07-09)
882

883
884
885
886
887
888
889
890
  * New feature:
    - The neverclaim parser now understands the new style of output
      used by Spin 6.24 and later.
  * Bug fixes:
    - The scc_filter() function could abort with a BDD error.  If all
      the acceptance sets of an SCC but the first one were useless.
    - The script in bench/spin13/ would not work on MacOS X because
      of some non-portable command.
891
    - A memory corruption in ltlcross.
892

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
893
New in spot 1.1.2 (2013-06-09)
894

895
896
897
898
899
  * Bug fixes:
    - Uninitialized variables in ltlcross (affect the count of terminal
      weak, and strong SCCs).
    - Workaround an old GCC bug to allow compilation with g++ <= 4.5
    - Fix several Doxygen comments so that they display correctly.
900

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
901
New in spot 1.1.1 (2013-05-13):
902

903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
  * New features:

    - lbtt_reachable(), the function that outputs a TGBA in LBTT's
      format, has a new option to indicate that the TGBA being printed
      is in fact a Büchi automaton.  In this case it outputs an LBTT
      automaton with state-based acceptance.

      The output of the guards has also been changed in two ways:
      1. atomic propositions that do not match p[0-9]+ are always
         double-quoted.  This avoids issues where t or f were used as
         atomic propositions in the formula, output as-is in the
         automaton, and read back as true or false.  Other names that
         correspond to LBT operators would cause problem as well.
      2. formulas that label transitions are now output as
         irredundant-sums-of-products.

    - 'ltl2tgba --ba --lbtt' will now output automata with state-based
      acceptance.  You can use 'ltl2tgba --ba --lbtt=t' to force the
      output of transition-based acceptance like in the previous
      versions.

      Some illustrations of this point and the previous one can be
      found in the man page for ltl2tgba(1).

927
928
929
930
931
932
    - There is a new function scc_filter_states() that removes all
      useless states from a TGBA.  It is actually an abbridged version
      of scc_filter() that does not alter the acceptance conditions of
      the automaton.  scc_filter_state() should be used when
      post-processing TGBAs that actually represent BAs.

933
934
935
936
937
938
939
940
941
    - simulation_sba(), cosimulation_sba(), and
      iterated_simulations_sba() are new functions that apply to TGBAs
      that actually represent BAs.  They preserve the imporant
      property that if a state of the BA is is accepting, the outgoing
      transitions of that state are all accepting in the TGBA that
      represent the BA.  This is something that was not preserved by
      functions cosimultion() and iterated_simulations() as mentionned
      in the bug fixes below.

942
943
944
    - ltlcross has a new option --seed, that makes it possible to
      change the seed used by the random graph generator.

945
946
947
948
949
950
951
952
    - ltlcross has a new option --products=N to check the result of
      each translation against N different state spaces, and everage
      the statistics of these N products.  N default to 1; larger
      values increase the chances to detect inconsistencies in the
      translations, and also make the average size of the product
      built against the translated automata a more pertinent
      statistic.

953
954
955
956
    - bdd_dict::unregister_all_typed_variables() is a new function,
      making it easy to unregister all BDD variables of a given type
      owned by some object.

957
  * Bug fixes:
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
958
959

    - genltl --gh-r generated the wrong formulas due to a typo.
960
961
    - ltlfilt --eventual and --universal were not handled properly.
    - ltlfilt --stutter-invariant would trigger an assert on PSL formulas.
962
963
    - ltl2tgba, ltl2tgta, ltlcross, and ltlfilt, would all choke on empty
      lines in a file of formulas.  They now ignore empty lines.
964
965
966
967
968
969
970
971
    - The iterated simulation applied on degeneralized TGBA was bogus
      for two reasons: one was that cosimulation was applied using the
      generic cosimulation for TGBA, and the second is that
      SCC-filtering, performed between iterations, was also a
      TGBA-based algorithm.  Both of these algorithms could lose the
      property that if a TGBA represents a BA, all the outgoing
      transitions of a state should be accepting.  As a consequence, some
      formulas where translated to incorrect Büchi automata.
972

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
973
New in spot 1.1 (2013-04-28):
974

975
976
977
978
979
980
981
  Several of the new features described below are discribed in

    Tomáš Babiak, Thomas Badie, Alexandre Duret-Lutz, Mojmír
    Křetínský, Jan Strejček: Compositional Approach to Suspension and
    Other Improvements to LTL Translation.  To appear in the
    proceedings of SPIN'13.

982
  * New features in the library:
983

984
985
986
    - The postprocessor class now takes an optional option_map
      argument that can be used to specify fine-tuning options, making
      it easier to benchmark different scenarios while developing new
987
988
      postprocessings.

989
990
991
992
993
994
    - A new translator class implements a complete translation chain,
      from LTL/PSL to TGBA/BA/Monitor.  It performs pre- and
      post-processings in addition to the core translation, and offers
      an interface similar to that used in the postprocessor class, to
      specify the intent of the translation.

995
996
997
998
    - The degeneralization algorithm has learned three new tricks:
      level reset, level caching, and SCC-based ordering.  The former
      two are enabled by default.  Benchmarking has shown that the
      latter one does not always have a positive effect, so it is
999
      disabled by default.  (See SPIN'13 paper.)
1000
1001
1002
1003

    - The scc_filter() function, which removes dead SCCs and also
      simplify acceptance conditions, has learnt how to simplify
      acceptance conditions in a few tricky situations that were not
1004
      simplified previously.  (See SPIN'13 paper.)
1005

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1006
1007
1008
1009
1010
1011
1012
1013
1014
    - A new translation, called compsusp(), for "Compositional
      Suspension" is implemented on top of ltl_to_tgba_fm().
      (See SPIN'13 paper.)

    - Some experimental LTL rewriting rules that trie to gather
      suspendable formulas are implemented and can be activated
      with the favor_event_univ option of ltl_simplifier.  As
      always please check doc/tl/tl.tex for the list of rules.

1015
1016
1017
1018
1019
    - An experimental "don't care" (direct) simulation has been
      implemented.  This simulations consider the acceptance
      of out-of-SCC transitions as "don't care".  It is not
      enabled by default because it currently is very slow.

1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
    - remove_x() is a function that take a formula, and rewrite it
      without the X operator.  The rewriting is only correct for
      stutter-insensitive LTL formulas (See K. Etessami's paper in IFP
      vol. 75(6). 2000) This algorithm is accessible from the
      command-line using ltlfilt's --remove-x option.

    - is_stutter_insensitive() takes any LTL formula, and check
      whether it is stutter-insensitive.  This algorithm is accessible
      from the command-line using ltlfilt's --stutter-insensitive
      option.

1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
    - Several functions have been introduced to check the
      strength of an SCC.
        is_inherently_weak_scc()
	is_weak_scc()
	is_syntactic_weak_scc()
	is_complete_scc()
	is_terminal_scc()
	is_syntactic_terminal_scc()

      Beware that the costly is_weak_scc() function introduced in Spot
      1.0, which is based on a cycle enumeration, has been renammed to
      is_inherently_weak_scc() to match established vocabulary.

1044
  * Command-line tools:
1045
1046

    - ltl2tgba and ltl2tgta now honor a new --extra-options (or -x)
1047
1048
1049
      flag to fine-tune the algorithms used.  The available options
      are documented in the spot-x (7) manpage.  For instance use '-x
      comp-susp' to use the afore-mentioned compositional suspension.
1050

1051
1052
1053
1054
1055
1056
    - The output format of 'ltlcross --json' has been changed slightly.
      In a future version we will offer some reporting script that turn
      such JSON output into various tables and graphs, and these change
      are required to make the format usable for other benchmarks (not
      just ltlcross).

1057
1058
1059
1060
    - ltlcross will now count the number of non-accepting, terminal,
      weak, and strong SCCs, as well as the number of terminal, weak,
      and strong automata produced by each tool.

1061
  * Documentation:
1062
1063

    - org-mode files used to generate the documentation about
1064
      command-line tools (shown at http://spot.lrde.epita.fr/tools.html)
1065
1066
1067
      is distributed in doc/org/.  The resulting html files are also
      in doc/userdoc/.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
  * Web interface:

    - A new "Compositional Suspension" tab has been added to experiment
      with compositional suspension.

  * Benchmarks:

    - See bench/spin13/README for instructions to reproduce our Spin'13
      benchmark for the compositional suspension.

1078
1079
  * Bug fixes:

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1080
1081
    - There was a memory leak in the LTL simplification code, that could
      only be triggered when disabling advanced simplifications.
1082

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1083
1084
    - The translation of the PSL formula !{xxx} was incorrect when xxx
      simplified to false.
1085

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1086
    - Various warnings triggered by new compilers.
1087

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1088
New in spot 1.0.2 (2013-03-06):
1089

1090
1091
1092
1093
  * New features:
    - the on-line ltl2tgba.html interface can output deterministic or
      non-deterministic monitors.  However, and unlike the ltl2tgba
      command-line tool, it doesn't different output formats.
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
    - the class ltl::ltl_simplifier now has an option to rewrite Boolean
      subformulaes as irredundante-sum-of-product during the simplification
      of any LTL/PSL formula.  The service is also available as a method
      ltl_simplifier::boolean_to_isop() that applies this rewriting
      to a Boolean formula and implements a cache.
      ltlfilt as a new option --boolean-to-isop to try to apply the
      above rewriting from the command-line:
      	    % ltlfilt --boolean-to-isop -f 'GF((a->b)&(b->c))'
	    GF((!a & !b) | (b & c))
      This is currently not used anywhere else in the library.
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
  * Bug fixes:
    - 'ltl2tgba --high' is documented to be the same as 'ltl2tgba',
      but by default ltl2tgba forgot to enable LTL simplifications based
      on language containment, which --high do enable.  There are now
      enabled by default.
    - the on-line ltl2tgba.html interface failed to output monitors,
      testing automata, and generalized testing automata due to two
      issues with the Python bindings.  It also used to display
      Testing Automaton Options when the desired output was set to Monitor.
    - bench/ltl2tgba would not work in a VPATH build.
    - a typo caused some .dir-locals.el configuration parameters to be
      silently ignored by emacs
    - improved Doxygen comments for formula_to_bdd, bdd_to_formula,
      and bdd_dict.
    - src/tgbatest/ltl2tgba (not to be confused with src/bin/ltl2tgba)
      would have a memory leak when passed the conflicting option -M
      and -O.  It probably has many other problems.  Do not use
      src/tgbatest/ltl2tgba if you are not writing a test case for
      Spot.  Use src/bin/ltl2tgba instead.
1123

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1124
New in spot 1.0.1 (2013-01-23):
1125

1126
1127
1128
1129
1130
1131
1132
1133
1134
  * Bug fixes:
    - Two executions of the simulation reductions could produce
      two isomorphic automata, but with transitions in a different
      order.
    - ltlcross did not diagnose write errors to temporary files,
      and certain versions of g++ would warn about it.
    - "P0.init" is parsed as an atomic even without the double quotes,
      but it was always output with double quotes.  This version will
      not quote this atomic proposition anymore.
1135
1136
1137
1138
    - "U", "W", "M", "R" were correctly parsed as atomic propositions
      (instead of binary operators) when placed in double quotes, but
      on output they were output without quotes, making the result
      unparsable.
1139
1140
    - the to_lbt_string() functions would always output a trailing space.
      This is not the case anymore.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1141
1142
    - tgba_product::transition_annotation() would segfault when
      called in a product against a Kripke structure.
1143
1144
1145
1146
1147
1148
  * Minor improvements:
    - Four new LTL simplifications rules:
        GF(a|Xb) = GF(a|b)
        GF(a|Fb) = GF(a|b)
        FG(a&Xb) = FG(a&b)
        FG(a&Gb) = FG(a&b)
1149
1150
    - The on-line version of ltl2tgba now displays edge and
      transition counts, just as the ltlcross tool.
1151
1152
    - ltlcross will display the number of timeouts at the end
      of its execution.
1153
1154
    - ltlcross will diagnose tools with missing input or
      output %-sequence before attempting to run any of them.
1155
1156
1157
1158
    - The parser for LBT's prefix-style LTL formulas will now
      read atomic propositions that are not of the form p1, p2...
      This makes it possible to process formulas written in
      ltl2dstar's syntax.
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
  * Pruning:
    - lbtt has been removed from the distribution.  A copy of the last
      version we distributed is still available at
        http://spot.lip6.fr/dl/lbtt-1.2.1a.tar.gz
      and our test suite will use it if it is installed, but the same
      tests are already performed by ltlcross.
    - the bench/ltl2tgba/ benchmark, that used lbtt to compare various
      LTL-to-Büchi translators, has been updated to use ltlcross.  It
      now output summary tables in LaTeX.  Support for Modella (no
      longer available online), and Wring (requires a too old Perl
      version) have been dropped.
    - the half-baked and underdocumented "Event TGBA" support in
      src/evtgba*/ has been removed, as it was last worked on in 2004.
1172

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1173
New in spot 1.0 (2012-10-27):
1174

1175
1176
1177
1178
  * License change: Spot is now distributed using GPL v3+ instead
    of GPL v2+.  This is because we started using some third-party
    files distributed under GPL v3+.

1179
1180
1181
1182
  * Command-line tools

    Useful command-line tools are now installed in addition to the
    library.  Some of these tools were originally written for our test
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1183
    suite and had evolved organically into useful programs with crappy
1184
1185
1186
    interfaces: they have now been rewritten with better argument
    parsing, saner defaults, and they come with man pages.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1187
    - genltl:   Generate LTL formulas from scalable patterns.
1188
1189
1190
1191
1192
1193
                This offers 20 patterns so far.

    - randltl:  Generate random LTL/PSL formulas.

    - ltlfilt:  Filter lists of formulas according to several criteria
                (e.g., match only safety formulas that are larger than
1194
1195
1196
1197
1198
		some given size).  Besides being used as a "grep" tool
		for formulas, this can also be used to convert
		files of formulas between different syntaxes, apply
		some simplifications, check whether to formulas are
		equivalent, ...
1199

1200
    - ltl2tgba: Translate LTL/PSL formulas into Büchi automata (TGBA,
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1201
                BA, or Monitor).  A fundamental change to the
1202
1203
1204
                interface is that you may now specify the goal of the
                translation: do you you favor deterministic or smaller
                automata?
1205
1206
1207

    - ltl2tgta: Translate LTL/PSL formulas into Testing Automata.

1208
    - ltlcross: Compare the output of translators from LTL/PSL to
1209
1210
1211
1212
                Büchi automata, to find bug or for benchmarking.  This
                is essentially a Spot-based reimplementation of LBTT
                that supports PSL in addition to LTL, and that can
                output more statistics.
1213

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1214
    An introduction to these tools can be found on-line at
1215
      http://spot.lrde.lip6.fr/tools.html
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1216
1217
1218

    The former test versions of genltl and randltl have been removed
    from the source tree.  The old version of ltl2tgba with its
1219
    gazillion options is still in src/tgbatest/ and is meant to be
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1220
1221
1222
    used for testing only.  Although ltlcross is meant to replace
    LBTT, we are still using both tools in this release; however this
    is likely to be the last release of Spot that redistributes LBTT.
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252

  * New features in the Spot library:

    - Support for various flavors of Testing Automata.

      The flavors are:
      + "classical" Testing Automata, as used for instance by
	Geldenhuys and Hansen (Spin'06), using Büchi and
	livelock acceptance conditions.
      + Generalized Testing Automata, extending the previous
	with multiple Büchi acceptance sets.
      + Transition-based Generalized Testing Automata moving Büchi
        acceptance to transitions, and getting rid of livelock
        acceptance conditions by expliciting stuttering self-loops.

      Supporting algorithms include anything required to run
      the automata-theoretic approach using testing automata:

      + dedicated synchronized product
      + dedicated emptiness-check for TA and GTA, as these
        may require two passes because of the two kinds of
	acceptance, while a TGTA can be checked for emptiness
	with the same one-pass algorithm as a TGBA.
      + conversion from a TGBA to any of the above kind, with
        options to reduce these automata with bisimulation,
	and to produce a BA/GBA that require a single pass
	(at the expense of determinism).
      + output in dot format for display

      A discussion of these automata, part of Ala Eddine BEN SALEM's
1253
      PhD work, should appear in ToPNoC VI (LNCS 7400).  The web-based
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1254
      interface and the aforementioned ltl2tgta tool can be used
1255
      to build testing automata.
1256
1257
1258
1259
1260
1261
1262

    - TGBA can now be reduced by Reverse Simulation (in addition to
      the Direct Simulation introduced in 0.9).  A function called
      iterated_simulations() will alternate direct and reverse
      simulations in a loop as long as it diminishes the size of the
      automaton.

1263
    - The enumerate_cycles class implements the Loizou-Thanisch
1264
1265
1266
1267
      algorithm to enumerate elementary cycles in a SCC.  As an
      example of use, is_weak_scc() will tell whether an SCC is
      inherently weak (all its cycles are accepting, or none of them
      are).
1268
1269
1270
1271
1272
1273

    - parse_lbt() will parse an LTL formula expressed in the prefix
      syntax used (at least) by LBT, LBTT and Scheck.
      to_lbt_string() can be used to print an LTL formula using this
      syntax.

1274
1275
1276
    - to_wring_string() can be used to print an LTL formula into
      Wring's syntax.

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1277
    - The LTL/PSL parser now has a lenient mode that can be useful
1278
1279
1280
1281
1282
1283
1284
      to interpret atomic proposition with language-specific constructs.
      In lenient mode, any (...) or {...} block that cannot be parsed
      as formula will be assumed to be an atomic proposition.
      For instance the input (a < b) U (process[2]@ok), normally
      flagged as a syntax error, is read as "a < b" U "process[2]@ok"
      in lenient mode.

1285
1286
1287
    - minimize_obligation() has a new option to disable WDBA
      minimization it cases it would produce a deterministic automaton
      that is bigger than the original TGBA.  This can help
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1288
      choosing between less states or more determinism.
1289
1290
1291
1292
1293
1294

    - new functions is_deterministic() and count_nondet_states()
      (The count of nondeterministic states is now displayed on
      automata generated with the web interface.)

    - A new class, "postprocessor", makes it easier to apply
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1295
      all available simplification algorithms on a TGBA/BA/Monitors.
1296
1297
1298
1299
1300
1301
1302
1303

  * Minor changes:

    - The '*' operator can (again) be used as an AND in LTL formulas.
      This is for compatibility with formula written in Wring's
      syntax.  However inside SERE it is interpreted as the Kleen
      star.

1304
1305
1306
1307
1308
1309
1310
    - When printing a formula using Spin's LTL syntax, we don't
      double-quote complex atomic propositions (that was not valid
      Spin input anyway).   For instance F"foo == 2" used to be
      output as <>"foo == 2".  We now output <>(foo == 2) instead.
      The latter syntax is understood by Spin 6.  It can be read
      back by Spot in lenient mode (see above).

1311
1312
1313
    - The gspn-ssp benchmark has been removed.


Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1314
New in spot 0.9.2 (2012-07-02):
1315

1316
1317
1318
  * New features to the web interface.
    - It can run ltl3ba (Babiak et al., TACAS'12) where available.
    - "a loading logo" is displayed when result is not instantaneous.
1319
1320
1321
1322
1323
  * Speed improvements:
    - The unicity hash table of BuDDy has been separated separated
      node table for better cache-friendliness.  The resulting speedup
      is around 5% on BDD-intensive algorithms.
    - A new BDD operation, called bdd_implies() has been added to
1324
      BuDDy to check whether one BDD implies another.  This benefits
1325
      mostly the simulation and degeneralization algorithms of Spot.
1326
1327
1328
    - A new offline implementation of the degeneralization (which
      had always been performed on-the-fly so far) available.  This
      especially helps the Safra complementation.
1329
1330
1331
  * Bug fixes:
    - The CGI script running for ltl2tgba.html will correctly timeout
      after 30s when Spot's translation takes more time.
1332
1333
1334
1335
1336
1337
    - Applying WDBA-minimization on an automaton generated by the
      Couvreur/LaCIM translator could lead to an incorrect automaton
      due to a bug in the definition of product with symbolic
      automata.
    - The Makefile.am of BuDDy, LBTT, and Spot have been adjusted to
      accomodate Automake 1.12 (while still working with 1.11).
1338
    - Better error recovery when parsing broken LTL formulae.
1339
1340
    - Fix errors and warnings reported by clang 3.1 and the
      upcoming g++ 4.8.
1341

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1342
New in spot 0.9.1 (2012-05-23):
1343

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1344
  * The version of LBTT we distribute includes a patch from Tomáš
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
    Babiak to count the number of non-deterministic states, and the
    number of deterministic automata produced.
    See lbtt/NEWS for the list of other differences with the original
    version of LBTT 1.2.1.
  * The Couvreur/FM translator has learned two new tricks.  These only
    help to speedup the translation by not issuing states or
    acceptance conditions that would be latter suppresed by other
    optimizations.
    - The translation rules used to translate subformulae of the G
      operator have been adjusted not to produce useless loops
      already implied by G.  This generalizes the "GF" trick
      presented in Couvreur's original FM'99 paper.
    - Promises generated for formula of the form P(a U (b U c))
      are reduced into P(c), avoiding the introduction of many
      promises that imply each other.
1360
1361
  * The tgba_parse() function is now available via the Python
    bindings.
1362
1363
1364
  * Bug fixes:
    - The random SERE generator was using the wrong operators
      for "and" and "or", mistaking And/Or with AndRat/OrRat.
1365
1366
    - The translation of !{r} was incorrect when this subformula
      was recurring (e.g. in G!{r}) and r had loops.
1367
    - Correctly recognize ltl2tgba's option -rL.
1368
1369
1370
1371
1372
1373
1374
    - Using LTL simplification rules based on syntactic implication,
      or based on language containment checks, caused BDD variables
      to be allocated in an "unnatural" order, resulting in a slower
      translation and a less optimal degeneralization.
    - When ltl2tgba reads a neverclaim, it now considers the resulting
      TGBA as a Büchi automaton, and will display double circles in
      the dotty output.
1375

Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1376
New in spot 0.9 (2012-05-09):
1377

1378
  * New features:
1379
1380
1381
1382
1383
1384
1385
1386
1387
    - Operators from the linear fragment of PSL are supported.  This
      basically extends LTL with Sequential Extended Regulat
      Expressions (SERE), and a couple of operators to bridge SERE and
      LTL.  See doc/tl/tl.pdf for the list of operators and their
      semantics.
    - Formula rewritings have been completely revamped, and augmented
      with rules for PSL operators (and some new LTL rules as well).
      See doc/tl/tl.pdf for the list of the rewritings implemented.
    - Some of these rewritings that may produce larger formulas
1388
      (for instance to rewrite "{a;b;c}" into "a & X(b & Xc)")
1389
1390
1391
1392
1393
1394
1395
1396
      may be explicitely disabled with a new option.
    - The src/ltltest/randltl tool can now generate random SEREs
      and random PSL formulae.
    - Only one translator (ltl2tgba_fm) has been augmented to
      translate the new SERE and PSL operators.  The internal
      translation from SERE to DFA is likely to be rewriten in a
      future version.
    - A new function, length_boolone(), computes the size of an
1397
1398
1399
1400
1401
1402
1403
      LTL/PSL formula while considering that any Boolean term has
      length 1.
    - The LTL/PSL parser recognizes some UTF-8 characters (like ◇ or
      ∧) as operators, and some output routines now have an UTF-8
      output mode.  Tools like randltl and ltl2tgba have gained an -8
      option to enable such output.  See doc/tl/tl.pdf for the list
      of recognized codepoints.
1404
    - A new direct simulation reduction has been implemented.  It
1405
      works directly on TGBAs.  It is in src/tgbaalgos/simlation.hh,
1406
      and it can be tested via ltl2tgba's -RDS option.
Alexandre Duret-Lutz's avatar
Alexandre Duret-Lutz committed
1407
    - unabbreviate_wm() is a function that rewrites the W and M operators
1408
1409
1410
1411
1412
      of LTL formulae using R and U.  This is called whenever we output
      a formula in Spin syntax.  By combining this with the aforementioned
      PSL rewriting rules, many PSL formulae that use simple SERE can be
      converted into LTL formulae that can be feed to tools that only
      understand U and R.  The web interface will let you do this.
1413
1414
1415
    - changes to the on-line translator:
      + SVG output is available
      + can display some properties of a formula
1416
1417
      + new options for direct simulation, larger rewritings, and
        utf-8 output